Liquid spray device for airplanes



Sept. 19, 1939. R. J. STREIF LIQUID SPRAY DEVICE FOR AIRPLANES FiledJan. 7, 1938 2 Sheets Shee-t 1\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\vv11: vl fl LIQUID INYENTOR R. J.Strei BY Q s K A j'oRNEY Sept. 19, 1939. J sTRElF 2,173,568

LIQUID SPRAYDEVICE FOR AIRPLANES Filed Jan. '7, 1938 2 Sheets-Sheet 2INVENTOR Patented Sept. 19, 1939 UNITED STATES PATENT OFFICE ApplicationJanuary 7,

8 Claims.

This invention relates to the forming and disbursing of a liquid sprayin fog like form over orchards and like agricultural areas by means ofan airplane flying over such areas.

The principal object of my invention is to provide a device for thepurpose, adapted to be mounted on the airplane and to be operated by theair stream from the propeller, so constructed that the minimum number ofmoving parts is 10 used, and wear and the possibility of troubledeveloping in service is minimized.

A further object is to provide a device of this character having liquidfeed means so arranged as to insure a very even distribution of theliquid N to the rotary unit and the spray forming nozzles thereon.

A further object of the invention is to produce a simple and inexpensivedevice and yet one which will be exceedingly effective for the purpose20 for which it is designed.

These objects I accomplish by means of such structure and relativearrangement of parts as will fully appear by a perusal of the followingspecification and claims.

In the drawings similar characters of reference indicate correspondingparts in the several views:

Figure l is a fragmentary outline of an airplane showing my improvedspray disburser 30 mounted thereon.

Figure 2 is a side elevation, partly in section of the main rear portionof the device.

Figure 3 is a fragmentary enlarged section on line 3-3 of Fig. 2.

Figure 4 is a cross section on line 4-4 of Fig. 3. Figure 5 is a frontelevation of the rear portion of the device, detached.

Referring now more particularly to the char-\ acters of reference on thedrawings, the driving unit of the device comprises front and rearpropellers I and 2 connected by a shaft 3. This shaft is turnablyenclosed in a housing 4 which is secured to the airplane on one sidethereof and rearwardly of the propeller 6 so that the 45 shaft 3 extendslengthwise of the airplane by suitable means such as struts I. It willbe understood that at least a pair of the units is mounted on theairplane, one on each side, in corresponding locations.

so Disposed immediately in front of the rear propeller 2 is an endlesscircular conduit 8,' preferably rectangular in cross section and openabout its inner periphery except for relatively small side flanges 9.This conduit is concentric with the shaft 3, and approaches thepropeller in 1938, Serial No. 183,805

diameter. It abuts against the leading edges of the blades of propeller2 and is suitably secured thereto so as to be rigid therewith. If theblades are metal, as is preferred (and as is the conduit), welding isthe securing means employed.

Projecting tangentially from the outer periphery of the conduit andlocated adjacent the various blades of the propeller are the tubular airand liquid intake, mixing and discharge nozzles. Each nozzle comprisesan open ended tube 10 projecting at one end into the conduit to about athird of its diameter and in the same direction as that in which theconduit rotates and which is determined by the direction of rotation ofthe propeller unit.

A transverse longitudinally extending partition II in the tube projectstoward the opposite end of the tube from said one end thereof, where itjoins and practically forms an unbroken tangential extension of theouter peripheral wall of the conduit. The nozzle tube is thus dividedinto a pair of spaced chambers l2 and I3, the former being incommunication at said one end of the tube with the interior of theconduit, and the latter at said end being exposed to the air outwardlyof the conduit. The opposite end of the tube is entirely outside theconduit, and is covered with a pair or more of removable fine meshscreens l4 held in place by a cap 15. A portion of the screens at thepoint furthest from the outer periphery of the conduit-or from thecentral shaftis cut away to leave an unobstructedopening l6 for thepurpose which will be shown.

By reason of the above described structure, it will be seen that ifliquid is fed into the revolving conduit from its inner open periphery,such liquid upon contacting with a wall of the conduit will be throwncentrifugally against the outer peripheral wall. The liquid naturallymoving at a slowerspeed than the conduit and nozzles, will be drawn intothe liquid chambers [2 of the latter. At the same time, as the nozzlesturn, air will be taken into corresponding ends of the outer chambersl3. At the termination of the partition II, which is ahead of thescreens, the air and liquid become mingled, and upon passing through thescreens are intimately mixed together and are discharged in the form ofa fine spray or fog. The liquid used for spray purposes frequentlycontains lead or other heavy matter which tends to precipitate and whichis incapable of passing through screens l4. Any such precipitatedmatter, upon leaving the outer ends 'of chambers I2 is at once throwncentrifugally to the radially outermost wall of the nozzle tubes.

Such matter is then in direct alinement with the screen openings I6, andwill be discharged through the same without clogging the screens. Thesize of these openings however is not sufllciently large to allow of anyappreciable amount of the mixture itself passing into the atmosphere.

The liquid is fed into the conduit in an even manner at horizontallyopposed points simultaneously by the following means: Extendingdownwardly toward the conduit from the supply tank on the airplane is afeed pipe I]. This is connected, directly above and in line with shaft3,.

with a downwardly curved transverse or lateral pipe It! at the center oflength thereof, this pipe l8 lying within the circular area defined bythe conduit. This pipe l8 terminates at both ends within the conduit 8 acertain distance substantially in horizontal alinement with shaft 3 asshown in Fig. 5. It will therefore be seen that liquid in equal volumeswill be fed into the conduit, so as to better insure all the nozzlesreceiving equal supplies of the liquid. I

It will also be seen that by reason of the manner in which feedingconnection between the conduit and pipe I8 is made, I avoid the need ofpacked joints or closely fitted parts, since the liquid will never tendto drop from the open inner side of the conduit, due to centrifugalaction, and the possible mingling of air with the liquid while thelatter is within the conduit will do no harm. The only parts of thestructure requiring careful and close fitting are the shaft 3 and itsbearings 19 within the sleeve 4and such features seldom if ever give anytrouble as is well known.

' The use of the two spaced propellers l and 2 secured together as aunit provides the necessary power for operating the disb urser withoutnecessitating the use of an unduly large propeller. I

From the foregoing description it will be readily seen that I haveproduced such a device as substantially fulfills the objects of theinvention as set forth herein.

While this specification sets forth in detail the present and preferredconstruction of the device, still in practice such deviations from suchdetail may be resorted to as do not form a departure from the spirit ofthe invention, as defined by the appended claims.

Having thus described my invention, what I claim as new and useful anddesire to secure by Letters Patent is:

1. A liquid spray device for airplanes compris ing an endless circularconduit disposed in a substantially vertical plane, means to rotate theconduit by the air stream set up by the movement of the airplane, adischarge nozzle connected to the conduit and projecting from the outerperiphery thereof, the conduit being open all about its inner periphery,a gravity-feed supply pipe terminating above the horizontal center ofthe conduit and gravity-feed branches connected to the pipe at saidtermination and extending downwardly to open terminations within theconduit substantially in the central horizontal plane thereof, saidbranches projecting through the inner peripheral opening of the conduit.

2. A liquid spray device for airplanes comprising an endless circularconduit disposed in a substantially vertical plane, means to rotate theconduit by the air stream set up by the movement of the airplane, meansto feed liquid into the conduit and a discharge nozzle connected to theconduit and projecting from the outer periphery thereof; said nozzlecomprising a tubular body and means dividing the body into a pair oflongitudinal chambers communicating with each other only adjacent theouter end of the body; one chamber at the inner end of the bodycommunicating with the interior of the conduit and. the other chamber atthe inner end of the body being open to atmosphere, and a mixing deviceat the outer end of the body.

3. A structure as in claim 2, in which said mixing device comprises afine-mesh screen unit across the body at its outer end.

4. A liquid spray device for airplanes comprising an endless circularconduit disposed in a substantially vertical plane, a discharge nozzleconnected to the conduit and projecting from the outer peripherythereof, means to feed liquid into the conduit and means to rotatetheconduit by the air stream set up by the movement of the airplane;said conduit'rotating means comprising a propeller adapted to be mountedon the airplane concentric with the conduit and against the blades ofwhich the conduit abuts in secured relation.

5. A liquid spray device for airplanes comprising an endless circularconduit disposed in a substantially vertical plane, means to rotate theconduit by the air stream set up by the movement of the airplane, meansto feed liquid into the conduit, a discharge nozzle connected to theconduit and projecting from the outer periphery thereof; said nozzlecomprising a tubular body cutting into the outer periphery of the bodysubstantially tangent thereto, the outer end of the body facing awayfrom the direction of rotation of the conduit, a transverse partitionextending lengthwise of the body from its opposite end and forming asubstantially tangential extension of the outer peripheral wall of theconduit, the corresponding end portion of the body radially outward ofthe partition being open to atmosphere, and a fine mesh screen acrossthe body at said outer end.

6. A liquid spray device for attachment to an airplane comprising atubular open ended body, means mounting said body for rotation about asubstantially horizontal axis to a radial line from which the body issubstantially tangent, means to rotate the body by the air stream set upby the movement of the air stream, a transverse partition in the body,said partition terminating short of that end of the body which facesopposite I the direction of rotation thereof, means to feed liquid intoone chamber formed by the partition, the other chamber at the oppositeend of the body being open to atmosphere, and a screen unit across thebody at the first named end thereof.

7. A structure as in claim 6, in which the screen unit is provided withan opening therethrough at the radially outermost point thereof.

8. A structure as in claim 6, in which an opening larger than thoseformed by the mesh of the screen is provided from the body adjacent thescreen at the radially outermost point thereof.

ROBERT J. STREIF.

